Genesis 41:53-56

And the seven years of plenteousness, that was in the land of Egypt, were ended.

The seven years of plenteousness ... ended. Over and above the proportion purchased for the government during the years of plenty, the people could still have husbanded much for future use. But improvident as men commonly are in the time of prosperity, they found themselves in want, and must have starved in thousands, had not Joseph anticipated and provided for the protracted calamity. The overflowing of the Nile being nature's substitute for rain in Egypt, has rendered the system of agriculture pursued special; and when the river is low, the irrigation is continued by artificial means.

The Nile begins to rise about the summer solstice, and the overflow commences two months after. Its greatest height is reached about the autumnal equinox, after which it gradually decreases, lasting in all three months. A 'good,' 'great,' or 'high' Nile is the precursor of an abundant season. A low inundation is followed by a deficient crop or a dearth. Too rapid a rise excites apprehension.

Last summer it was fourteen feet higher than the preceding year at the same date, when it had yet forty-five days to rise. The government despatched by rail a great quantity of timber and piles to different point, to be ready to dam the gaps, in case the dykes gave way; and men were employed in raising the banks along the river.

The hopes of the country depend upon the proper economy and distribution of the water. Dearths from a failure of inundation are far from being unfrequent in the history of modern Egypt. One famine is recorded of seven years' duration, A.D. 1064 AD - 1071 AD, when the greatest misery prevailed. From such a frightful state of destitution the heaven-inspired foresight of Joseph preserved his age.

We now know (Burton and Speke's 'Journal') that the source of the Nile is Lake Nyanza, which is fed by streams that issue from the 'Montes Lunae,' and that the rise and fall of that river is owing not, as was supposed to the melting of mountain snows, but to the tropical rains which periodically fall in the lake region. In the time of Joseph there was a disturbance of the overflow.

'The waters of the flood, for seven years together, very far exceeded all that had ever before been known in Egypt; so that an extent of surface was brought under cultivation in the Delta unparalleled at any former or subsequent period. This again was followed by seven years, during which "there was neither earing nor harvest" - expressions which leave us surely to infer that in the course of them the phenomenon never appeared at all. The discharge or bursting of the Lake of Ethiopia may have been the natural cause of the seven years' plenty, and the re-action produced by the entire drainage of the lake, which would leave a vast expanse of mud exposed to the tropical sun the consequent occasion of the seven years' famine. When it is further explained that this hypothesis, as to the condition of the bottom of the lake, is exactly that which the present state of the plain of Darfur clearly indicates to have actually prevailed, a strong case, prima facie, is made out, that the proximate natural cause of the seven years of plenty and famine was the bursting of the Lake of Ethiopia. When we state, in addition, that one of the obscure contemporary and rival kings of Aphophis, the patron of Joseph, registered the rise of the lake in Nubia and Ethiopia up to the very year of its disruption, as it would seem, we find that the plenty and famine were like the rest of the divine dealings in Egypt, actual occurrences, the natural causes of which were foreknown and predisposed' (Osburn's 'Mon. Hist.,' vol. 2:, pp. 135-9).